I personally like PostgreSQL because its an open source database, I was introduce first when Kamran Azeem told me about its power & strength; But as I am Oracle certified DBA & have a long term experience i personally admit its the best in the world. "No doubt" but for the users/managers those are using oracle for not highly critical system, i would recommend them for Postgresql.
Today I was talking with Mauro (my office's dba) he was amazed when he came to know about postgresql powers & design. After our almost 20min discussion he agreed to use Postgresql for some logs management instances. He asked me to find out the benchmark/comparison between Oracle VS Postgresql, after a 10-15min googling I cam across this article it even covers mysql comparison.
Its not a bad idea for any of you to try Postgresql...although its not Oracle but of course something near to it. **Just for Free** :)